Process of creaseproofing cellulose fabrics with 2, 6-dioxaspiro (3, 3) heaptane and ormaldehyde and fabrics produced thereby



United States Patent PROCESS OF CREASEPROOFIIIG CELLULOSE FAB- RICS WITH 2,6-DlXASPIRO(3,3)HEPTANE AND FORMALDEHYDE AND FABRICS PRODUCED TI-HEREBY Mei /in D. Hurwitz, Southampton, and Stella Y. Wang, Philadelphia, Pa, assignors to Rohm & Haas Company, Philadelphia, Pa, a corporation of Delaware No Drawing. Filed Dec. 28, 1959, Ser. No. 862,041

12 Claims. (Cl. 8-116A) This invention rel-ates to the treatment of cellulosic fabrics, such as those of cotton and regenerated cellulose rayon, for the purpose of imparting to them increased resilience, improved recovery from creasing, wrinkling, and other deformations, and the characteristic of having reduced shrinkage on washing so that partial or complete dimensional stabilization may be effected. It is also concerned with producing cellulosic fabrics whose improved properties of the type just mentioned are durable. The invention also embraces the treated fabrics obtained.

In accordance with the disclosure of United States application Serial No. 689,788, filed October 14, 1957, now US. Patent 3,024,080, in the hands of a common assignee, cellulosic fabrics, woven, knitted, or otherwise formed, having reduced shrinkage on washing and improved resistance to creasing and crushing are obtained when they are treated with 2,6-dioxaspiro(3,3)heptane of the formula For convenience, this compound will be hereinafter referred to by the shorter term diox'aspiroheptane.

It is also known that treatment with formaldehyde improves the crease resistance of cellulosic fabrics but this treatment embrittles the fabric. It has now been found that improvement in crease resistance and the other properties mentioned above can be obtained by the simultaneous application of the dioxaspiroheptane and formaldehyde without the disadvantages normally associated with the use of formaldehyde for this purpose. In this manner, it is possible to reduce the amount of the expensive dioxaspiroheptane to one-third of the amount thereof which would be required, if used alone, to obtain a given effect without running into difiiculties with embrittlement.

The treatment with dioxaspiroheptane and formaldehyde may be effected most advantageously by means of aqueous solutions thereof in which the dioxaspiroheptane and formaldehyde are dissolved at a concentration which may vary from 1 to 15% by weight of diox-aspiroheptane and l to of formaldehyde. Preferably, the concentration is from 3 to 7% by weight of dioxaspiroheptame and 2 to 4% of formaldehyde to obtain the maximum benefits in crease-proofing and the like.

The treatment with dloxaspiroheptane and formaldehyde is carried out in the presence of a catalyst. Effective catalysts are metal salts of acids having the composition H,(XY,,), where H is hydrogen, a is an integer which depends on the valence of the complex ion and may have a value of l to 3, X is a non-metal selected from the group consisting of boron, silicon, sulfur, and chlorine, said non-metal being in a state where its valence is from 3 to 7, Y is fluorine or oxygen, and b is an integer having a value of 4 or 6. The metals of these salts are those of groups Ib, II, 11112, IV, and VIII of the periodic table in T. Moeller, Inorganic Chemistry, John Wiley &

3,097,050 Patented July 9, 1963 ice Sons, New York, 1952, which have an atomic weight of at least 12. Salts of perchloric and fluoboric acids are very eflicient catalysts, particularly their zinc, lead, copper, and magnesium compounds. Salts of sulfuric acid, such as aluminum and copper sulfate, and of fluosilicic acid, such as magnesium, zinc, and copper fluosilicates, also are active as catalysts. Other acidic compounds, oxalic acid, for example, may also be used as catalysts.

Conveniently, the mount of catalyst may vary from about 0.2 to 2% and is preferably in the range of 0.5 to 1% concentration in the aqueous solution of dioxaspiroheptane and formaldehyde.

The catalyzed solution of dioxaspiroheptane and formaldehyde is compatible with solutions or dispersions of most of the common textile finishing agents, such as synthetic polymer latices, silicone resins, and aminoplast resins or precondensates, so that they may also be applied simultaneously to produce changes in the hand or other properties of the fabric.

The aqueous solution containing dioxaspiroheptane, formaldehyde, and catalyst may be applied to the fabric in any suitable manner such as by spraying or impregnation. In general, it is preferable to use some method of impregnation. With piece goods, this is conveniently carried out with the various machines used for treating fabrics in open width, such as pads or jigs. However, it is not required that the impregnation be carried out in open width, and the fabric may be handled in any form. In treating garments or other articles made from cellulosic fabrics, the impregnation may be carried out in a tumble wheel, laundry machine, or other suitable equipment. After application of the solution, it is desirable to remove the excess solution by squeezing the fabric between rollers, or by shaking or centrifuging it, in order to insure a more even treatment. The fabric treated with solution may be dried, such as by air-drying at normal room temperature or by heating in a drying oven at temperatures of F. and up. The drying and curing operations are preferably done with the fabric open and flat, so that it will have a smooth and even appearance when finished. In a preferred embodiment, the impregnated fabric, immediately after impregnation and without preliminary low-temperature drying, is carried in open width by a tenter frame through a curing oven where it is subjected to temperatures of about 250 F. to about 400 F. or higher for a period of time ranging from about one minute to about one-half hour or more, the shorter period being employed at the higher temperature and vice versa. Entirely satisfactory results are obtained by heating for five to ten minutes at about 300 F. This cuning operation not only dries the impregnated fabric but apparently causes a reaction between the dioxaspiroheptane, formaldehyde, and the hydroxyl groups of the cellulose. The action of each of the two reagents apparently infiuences the action of the other synergistically. It is not intended, however, that the present invention be limited to this theory of operation.

The treated fabrics exhibit a high degree of crush resistance and crease recovery with little or no change in the hand or feel of the fabric. The treatment does not discolor the fabric. In addition, the treated fabrics have the important advantage that they do not retain chlorine, so that the use of bleaching agents containing chlorine does not cause deterioration either by way of discoloration or loss in tensile strength even when the treated fabrics which have been bleached are subjected to ironing temperatures. The treated fabrics are also resistant to shrinkage during laundering, and the treatment is very permanent towards laundering, dry-cleaning, and other procedures for cleaning textile fabrics.

The following examples illustrate the present invention,

and the parts and percentages therein are by weight unless otherwise noted. The crease recovery values given below were determined by the Shirley Institute procedure (British. Standards Handbook No. 11, 1949 ed., page 128).

EXAMPLE 1 (a) A sample of cotton printcloth was saturated with an aqueous solution containing 3% dioxaspiroheptane, 4% of formaldehyde, and 1% zinc fluoborate. It was dried at 105 C. for five minutes and then put into an oven at 150 C. and baked for ten minutes. A control treated with an aqueous 4% solution of formaldehyde containing 1% zinc fluoborate was similarly prepared. After being conditioned, the samples had the following crease recovery values:

Table A I Warp I Fill Average Formaldehyde Control 110 109 110 Dioxaspirpheptane and HCI'IO 123 122 123 Treatment in the same way with a solution containing 1% zinc fluoborate and dioxaspiroheptane above required 15% of the latter to attain a crease recovery of 123.

(b) After ten commercial launderings, the crease recovery and tensile strength of the fabrics obtained in part (a) were essentially unchanged.

EXAMPLE 2 (a) The procedure of Example 1 is repeated substituting 1% of zinc perchlorate for the zinc fluoborate. Similar crease recovery results were obtained.

(b) The procedure of Example 1 is repeated using rayon challis instead of cotton printcloth. The treated fabric was insoluble in cuprammonium hydroxide and had a crease recovery of 120 C.

EXAMPLE 3 Samples of cotton printcloth were treated with aqueous solutions of dioxaspiroheptane and formaldehyde at various concentrations, each solution containing 1.0% of zinc fluoborate as catalyst and then baked at 150 C. for 15 minutes. Water and catalyst controls were also prepared. The same were conditioned and tested for crease recovery with the following results:

Table B Concentration (percent) Crease Recovery (Degrees) Dioxaspiro- Average of heptane HCHO Warp and Fill 4 2,6-dioxaspiro(3,3)heptane, 2 to 4% by weight of formaldehyde, and 0.2 to 2% by weight of a catalyst selected from the group consisting of metal salts of an acid of the formula H (XY where H is hydrogen, a is an integer having a value of 1 to 3, X is a member selected from the group consisting of boron, silicon, sulfur, and chlorine, Y is a member selected from the group consisting of fluorine and oxygen, and b is an integer selected from 4 and 6, said metal being selected from the group consisting of those in groups Ib, II, I'IIb, IV, and VIII of the periodic table, the cellulose-reactive substances in the solution consisting essentially entirely of the aforesaid heptane and formaldehyde, drying and heating the impregnated fabric at a temperature of about 250 to 400 F, until the crease resistance of the fabric is increased.

2. A process as defined in claim 1 in which the fabric is cotton.

3. A process as defined in claim 1 in which the fabric is a regenerated cellulose rayon.

4. As an article of manufacture, a textile fabric obtained by the process of claim 1 which comprises a reaction product of a cellulose fabric with formaldehyde and 2,6-dioxaspiro(3,3)heptane and has an increased crease resistance as compared to the initial cellulose fabric.

5. An article as defined in claim 4 in which the fabric is a cotton fabric.

6. An article as defined in claim 4 in which the fabric is a regenerated cellulose fabric.

7. The process consisting of impregnating a cellulose fabric with an aqueous solution containing 3 to 7% by Weight of 2,6-dioxaspiro(3,3)heptane, 2 to 4% of formaldehyde, and 0.2 to 2% of Zinc perchlorate, the cellulosereactive substances in the solution consisting essentially entirely of the aforesaid heptane and formaldehyde, drying and heating the impregnated fabric at a temperature of about 250 to 400 F. until the crease resistance of the fabric is increased.

8. A process as defined in claim 7 is cotton.

9. A process as defined in claim 7 in which the fabric is a regenerated cellulose rayon.

10. The process consisting of impregnating a cellulose fabric with an aqueous solution containing 3 to 7% by Weight of 2,6-dioxaspiro(3,3)heptane, 2 to 4% of formaldehyde, and 0.2 to 2% of zinc fluoborate, the cellulosereactive substances in the solution consisting essentially entirely of the aforesaid heptane and formaldehyde, drying and heating the impregnated fabric at a temperature of about 250 to 400 F. until the crease resistance of the fabric is increased.

111. A process as defined in claim 10 in which the fabric is cotton.

12. A process according to claim 10 in which the fabric s a regenerated cellulose rayon.

in which the fabric References Cited in the file of this patent UNITED STATES PATENTS 2,108,520

OTHER REFERENCES Hall: American Dyestuff Reporter, June 19, 1933, pp. 379-381 and 399-401.

Gruntfest: Textile Research Journal, November 1948, pp. 643-650. 

1. THE PROCESS CONSISTING OF IMPREGNATING A CELLULOSE FABRIC WITH AN AQUEOUS SOLUTION OF 3 TO 7% BY WEIGHT OF 2,6-DIOXASPIRO(3,3)HEPTANE, 2 TO 4% BY WEIGHT OF FORMALDEHYDE, AND 0.2 TO 2% BY WEIGHT OF A CATALYST SELECTED FROM THE GROUP CONSISTING OF METAL SALTS OF AN ACID OF THE FORMULA HA(XYB) WHERE H IS HYDROGEN, A IS AN INTEGER HAVING A VALUE OF 1 TO 3, X IS A MEMBER SELECTED FROM THE GROUP CONSISTING OF BORON, SILICON, SULFUR, AND CHLORINE, Y IS A MEMBER SELECTED FROM THE GROUP CONSISTING OF FLUORINE AND OXYGEN, AND B IS AN INTEGER SELECTED FROM 4 AND 6, SAID METAL BEING SELECTED FROM THE GROUP CONSISTING OF THOSE IN GROUPS IB, II, IIIB, IV, AND VIII OF THE PERIODIC TABLE, THE CELLULOOSE-REACTIVE SUBSTANCES IN THE SOLUTION CONSISTING ESSENTIALLY ENTIRELY OF THE AFORESAID HEPTANE AND FORMALDEHYDE, DRYING AND HEATING THE IMPREGNATED FABRIC AT A TEMPERATURE OF ABOUT 250* TO 400*F., UNTIL THE CREASE RESISTANCE OF THE FABRIC IS INCREASED. 